Industrial Refrigeration Oil Service

Anindustrial refrigeration oil service visit was arranged because of an oil return issue. Several fans had been down on the air cooled chilled water system. This causes the chilled water system to unload so as to prevent a fault occurring. The lower mass flow rate of the refrigerant caused oil to migrate to the low side of the system. Several vessels are available with various forms oil oil return control. These vessels were valved off. A two man team with the correct ammonia PPE and breathing apparatus carried out the job

Not Enough Oil Recovered During Service to the Industrial Refrigeration Plant

Only some of the oil was recovered using during the industrial refrigeration service of the plant. Therefore, the engineers decided to add new oil to get the chilled water system running. The only problem with doing this is that once running the machine, the oil has to be got back out. Therefore, the industrial refrigeration oil service had to be carried out a second time to resolve the oil return issue

Chilled Water System Repair by Fitting Fan Decks

For this chilled water system repair, scaffolding had been erected in accordance with the Risk Assessment. The old fan decks were lifted out by the two man team. A really good team was sent out: one of the men was more technical and the other more mechanical- complementing each other with their different skill sets. The new fans were an updated version and the wiring was different. The fault link has to be adapted but the 0-10v input from the controller was the same. The controller reads the pressure from a transducer, then sends out a voltage which the fan turns into the corresponding speed

Service Testing of the Chilled Water System

The fault link had been correctly modified so service testing of the chilled water system was carried out. The machine loaded up to 62% and monitoring continued during the rest of the visit

Tick Sheet for the Industrial Refrigeration Service Visit

The industrial refrigerationservicevisit is carried out inside a walk in room so some of the machine can be serviced in the dry, good job because it is a bit of a rainy day- don't want to get the tick sheet wet!

Chiller Controller

The controller for theplant hasbeen problematic from when the chiller was first lifted in. It faults out regularly: reoccuring known faults known to the customer. Part of the problem are low load conditions. This causes the chiller to go into various alerts then it eventually trips out

Over Complicated Program for the PLC

Another part of the problem are over complicated controls. I often think about the same machine in a critical process environment. This machine is bespoke so there will be a bog standard version as well. The controls on this version have too many sensors, generating too many faults. There is always something which trips it out when no fault as such is present. The controls themselves are a fault if they are problematic. Factory Managers don't like too many industrial refrigeration service visits because of spurious trip outs- they just want the plant to just run seamlessly. This customer, however, has to pay for more parts and more industrial refrigeration service is to keep it running

Trim the Ammonia Refrigerant

The chiller has a low refrigerant charge so an industrial refrigeration service visit has been arranged to trim the ammonia refrigerant. We have state of the art ammonia refrigerant recovery units Read More but these are used when handling tonnes of ammonia refrigerant. This is just a small 200kw industrial refrigeration plant so we will be using a smaller ammonia refrigerant recovery method

Oil Return During the Industrial Refrigeration Service Visit

Low refrigerant charge diagnosed during the industrial refrigeration service visit causing the oil to migrate to the low side of the system. The oil will need to be manually recovered from various vessels following the ammonia oil recovery procedure

Industrial Refrigeration Service Welding of the Pipework

The ammonia had been removed to perform industrial refrigeration servicewelding. This was carried out using the zero-zero breaking in procedure. This visit was to replace rusted pipework. The welder got strait to it: grinding out the components ready for the welding. After the welding was completed, the vessel was leak tested and pressure tested. Another part of the system which contained liquid required works so:

Ammonia Refrigerant Transfer Pump

The ammonia refrigerant transfer pump failed during therecovery of 6 tonnes of anhydrous ammonia. There was a tight schedule as delays would mean less time for the upgrade during factory shutdown. Our engineer quickly took the side covers off the ammonia refrigerant transfer pump. He found that the coupling had come loose. Luckily, he found it to be not damaged more than scratches. Therefore, he bolted it together again and tested it: back in production

Shell and Tube Service

After the above was carried out- the plant was inspected. The condenser had failed on the industrial refrigeration plant. Ammonia had been leaking into the water system causing the ammonia warning alarm being triggered with plant shut down

Burst Tubes

Our shell and tube technician identified the tubes. Then, industrial refrigeration service welding was carried out on the burst ones. Dehydration was easy as the ammonia refrigerant had been leaking out with not much water getting in. Also, the water system was drained prior to removing the refrigerant

Run Testing

The customer signed off the paperwork for the job. The readings were monitored for some time to look for any abnormalities. All readings were okay- another happy customer!

Are you a factory manager or facility manager? Have you got service issues with your industrial refrigeration plant? Bills too high? For service: Maximus Chillers can help Click Here

For the International Institute of Ammonia Refrigeration (IIAR) Click Here